Three wetlands constructed in 1995 on land adjacent to agricultural fields in northwest Ohio were allowed to establish vegetation passively. Survey data collected 1998-2001 from quadrats in open water, frequently and infrequently submerged zones within the basin, identified 77 species over the three sites. Greatest species diversity occurred in the infrequently and frequently submerged zones. The dominant species within the wetlands originated from agricultural fields, nearby drainage ditches, streams, and the seeded erosion control buffer zones surrounding the wetlands. Six years following
construction, less than 50% of the dominant species were wetland species. Results suggest that for constructed wetlands in agricultural settings, plantings or seeding of desired species will be required to
supplement the existing sources of wetland vegetation species.